Add the real benchmarks comparing lldb against gdb for repeated expression evaluations.

Modify lldbbench.py so that lldbtest.line_number() utility function is available to
BenchBase client as just line_number(), and modify lldbtest.py so that self.lldbExec
(the full path for the 'lldb' executable) is available to BenchBase client as well.

An example run of the test case on my MacBook Pro running Lion:

1: test_compare_lldb_to_gdb (TestRepeatedExprs.RepeatedExprsCase)
   Test repeated expressions with lldb vs. gdb. ... 
lldb_avg: 0.204339
gdb_avg: 0.205721
lldb_avg/gdb_avg: 0.993284
ok

llvm-svn: 136740

lldb/test/benchmarks/example/TestRepeatedExprs.py

@@ -1,6 +1,6 @@
 """Test evaluating expressions repeatedly comparing lldb against gdb."""
 
-import os
+import os, sys
 import unittest2
 import lldb
 import pexpect
@@ -10,28 +10,118 @@ class RepeatedExprsCase(BenchBase):
 
     mydir = os.path.join("benchmarks", "example")
 
-    @benchmarks_test
-    def test_with_lldb(self):
-        """Test repeated expressions with lldb."""
-        self.buildDefault()
-        self.run_lldb_repeated_exprs()
+    def setUp(self):
+        BenchBase.setUp(self)
+        self.source = 'main.cpp'
+        self.line_to_break = line_number(self.source, '// Set breakpoint here.')
+        self.lldb_avg = None
+        self.gdb_avg = None
 
     @benchmarks_test
-    def test_with_gdb(self):
-        """Test repeated expressions with gdb."""
+    def test_compare_lldb_to_gdb(self):
+        """Test repeated expressions with lldb vs. gdb."""
         self.buildDefault()
-        self.run_gdb_repeated_exprs()
+        self.exe_name = 'a.out'
 
-    def run_lldb_repeated_exprs(self):
-        for i in range(1000):
+        print
+        self.run_lldb_repeated_exprs(self.exe_name, 100)
+        self.run_gdb_repeated_exprs(self.exe_name, 100)
+        print "lldb_avg: %f" % self.lldb_avg
+        print "gdb_avg: %f" % self.gdb_avg
+        print "lldb_avg/gdb_avg: %f" % (self.lldb_avg/self.gdb_avg)
+
+    def run_lldb_repeated_exprs(self, exe_name, count):
+        exe = os.path.join(os.getcwd(), exe_name)
+
+        # Set self.child_prompt, which is "(lldb) ".
+        self.child_prompt = '(lldb) '
+        prompt = self.child_prompt
+
+        # So that the child gets torn down after the test.
+        self.child = pexpect.spawn('%s %s' % (self.lldbExec, exe))
+        child = self.child
+
+        # Turn on logging for what the child sends back.
+        if self.TraceOn():
+            child.logfile_read = sys.stdout
+
+        child.expect_exact(prompt)
+        child.sendline('breakpoint set -f %s -l %d' % (self.source, self.line_to_break))
+        child.expect_exact(prompt)
+        child.sendline('run')
+        child.expect_exact(prompt)
+        expr_cmd1 = 'expr ptr[j]->point.x'
+        expr_cmd2 = 'expr ptr[j]->point.y'
+
+        # Reset the stopwatch now.
+        self.stopwatch.reset()
+        for i in range(count):
             with self.stopwatch:
-                print "running "+self.testMethodName
-                print "benchmarks result for "+self.testMethodName
-        print "stopwatch:", str(self.stopwatch)
+                child.sendline(expr_cmd1)
+                child.expect_exact(prompt)
+                child.sendline(expr_cmd2)
+                child.expect_exact(prompt)
+            child.sendline('process continue')
+            child.expect_exact(prompt)        
+
+        child.sendline('quit')
+        try:
+            self.child.expect(pexpect.EOF)
+        except:
+            pass
+
+        self.lldb_avg = self.stopwatch.avg()
+        if self.TraceOn():
+            print "lldb expression benchmark:", str(self.stopwatch)
+        self.child = None
+
+    def run_gdb_repeated_exprs(self, exe_name, count):
+        exe = os.path.join(os.getcwd(), exe_name)
+
+        # Set self.child_prompt, which is "(gdb) ".
+        self.child_prompt = '(gdb) '
+        prompt = self.child_prompt
+
+        # So that the child gets torn down after the test.
+        self.child = pexpect.spawn('gdb %s' % exe)
+        child = self.child
+
+        # Turn on logging for what the child sends back.
+        if self.TraceOn():
+            child.logfile_read = sys.stdout
+
+        child.expect_exact(prompt)
+        child.sendline('break %s:%d' % (self.source, self.line_to_break))
+        child.expect_exact(prompt)
+        child.sendline('run')
+        child.expect_exact(prompt)
+        expr_cmd1 = 'print ptr[j]->point.x'
+        expr_cmd2 = 'print ptr[j]->point.y'
+
+        # Reset the stopwatch now.
+        self.stopwatch.reset()
+        for i in range(count):
+            with self.stopwatch:
+                child.sendline(expr_cmd1)
+                child.expect_exact(prompt)
+                child.sendline(expr_cmd2)
+                child.expect_exact(prompt)
+            child.sendline('continue')
+            child.expect_exact(prompt)        
+
+        child.sendline('quit')
+        child.expect_exact('The program is running.  Exit anyway?')
+        child.sendline('y')
+        try:
+            self.child.expect(pexpect.EOF)
+        except:
+            pass
+
+        self.gdb_avg = self.stopwatch.avg()
+        if self.TraceOn():
+            print "gdb expression benchmark:", str(self.stopwatch)
+        self.child = None
 
-    def run_gdb_repeated_exprs(self):
-        print "running "+self.testMethodName
-        print "benchmarks result for "+self.testMethodName
 
 if __name__ == '__main__':
     import atexit

lldb/test/benchmarks/example/main.cpp

@@ -30,13 +30,13 @@ int main(int argc, char const *argv[]) {
     }
 
     printf("Finished populating data.\n");
-    for (int i = 0; i < 1000; ++i) {
+    for (int j = 0; j < 1000; ++j) {
         bool dump = argc > 1; // Set breakpoint here.
                               // Evaluate a couple of expressions (2*1000 = 2000 exprs):
-                              // expr ptr[i]->point.x
-                              // expr ptr[i]->point.y
+                              // expr ptr[j]->point.x
+                              // expr ptr[j]->point.y
         if (dump) {
-            printf("data[%d] = %d (%d, %d)\n", i, ptr[i]->id, ptr[i]->point.x, ptr[i]->point.y);
+            printf("data[%d] = %d (%d, %d)\n", j, ptr[j]->id, ptr[j]->point.x, ptr[j]->point.y);
         }
     }
     return 0;

lldb/test/lldbbench.py

@@ -1,6 +1,7 @@
 import time
-from lldbtest import benchmarks_test
 from lldbtest import Base
+from lldbtest import benchmarks_test
+from lldbtest import line_number
 
 class Stopwatch(object):
     """Stopwatch provides a simple utility to start/stop your stopwatch multiple
@@ -80,7 +81,7 @@ class Stopwatch(object):
         return self.__total_elapsed__ / self.__laps__
 
     def __str__(self):
-        return "Avg: %f (Laps: %d, Total Elapsed Time: %d)" % (self.avg(),
+        return "Avg: %f (Laps: %d, Total Elapsed Time: %f)" % (self.avg(),
                                                                self.__laps__,
                                                                self.__total_elapsed__)
 

lldb/test/lldbtest.py

@@ -451,6 +451,9 @@ class Base(unittest2.TestCase):
         #import traceback
         #traceback.print_stack()
 
+        if "LLDB_EXEC" in os.environ:
+            self.lldbExec = os.environ["LLDB_EXEC"]
+
         # Assign the test method name to self.testMethodName.
         #
         # For an example of the use of this attribute, look at test/types dir.
@@ -837,9 +840,6 @@ class TestBase(Base):
         # Works with the test driver to conditionally skip tests via decorators.
         Base.setUp(self)
 
-        if "LLDB_EXEC" in os.environ:
-            self.lldbExec = os.environ["LLDB_EXEC"]
-
         try:
             if lldb.blacklist:
                 className = self.__class__.__name__